Show Notes
How We Eat Most of us think we know what we eat. However, nutrition researchers have learned a frustrating lesson over the years: asking people what they ate yesterday is often less accurate than anyone would like. Although food diaries and surveys can provide useful information, memories are imperfect, snacks are easily forgotten, and portion sizes tend to grow smaller in retrospect. Consequently, some of the most important nutrition research takes place in a setting that is both expensive and surprisingly simple—a metabolic ward, where every meal is prepared, every serving is weighed, and every leftover bite is measured. That approach is exactly what researcher Kevin Hall and his colleagues used in a landmark study at the NIH. Participants were given two different diets, one based largely on ultra-processed foods and another built around minimally processed foods. Importantly, the volunteers could eat as much as they wanted. Nobody instructed them to count calories, restrict portions, or lose weight. Nevertheless, participants consumed about 500 more calories per day when eating the ultra-processed diet. The same people, living in the same environment, produced dramatically different results simply because the food changed.
Obesity in the US and Ultra-Processed Foods As a result, the study raised an intriguing question. If ultra-processed foods can influence calorie intake to that degree, why isn't everyone obese? After all, ultra-processed foods make up a large portion of the modern food supply. Grocery stores are filled with them, convenience stores specialize in them, and many restaurants depend on them. Yet despite widespread exposure to the same food environment, some people seem relatively unaffected while others struggle with appetite, cravings, and weight gain.
Prego and Vanishing Calories To understand how we arrived here, it helps to step back a few decades. During the latter half of the twentieth century, food companies increasingly turned to scientists, statisticians, and sensory researchers to understand consumer behavior. One of the most influential figures was Howard Moskowitz, a researcher who discovered that there was no single perfect food. Instead, he found that consumers tended to cluster into different preference groups. Some people preferred sweeter products, others wanted more texture, and still others favored stronger flavors. As a result, food manufacturers stopped searching for one ideal product and began creating multiple versions designed to appeal to different consumers. Meanwhile, another researcher, Steven Witherly, focused on a different question. Rather than asking what people preferred, he explored why certain foods were so rewarding. His work highlighted the importance of texture, aroma, crunch, temperature, and mouthfeel. In other words, food is not simply taste. Instead, it is a complex sensory experience involving multiple signals that influence how satisfying a meal feels. One of Witherly's most memorable concepts is known as vanishing caloric density. Certain foods, particularly puffed snacks, dissolve quickly in the mouth and create the sensation that they have almost disappeared. Although the calories remain, the physical experience of eating them can feel surprisingly brief. Consequently, these foods may be easier to consume in larger quantities before the body's normal satiety signals fully catch up. While that does not make such foods inherently bad, it does help explain why some snacks seem to empty themselves once the bag is opened.
Ultra-Processed Foods and GLP-1 At the same time, the modern food environment has become remarkably effective at attracting attention. Food manufacturers optimize texture, flavor, aroma, and convenience, while consumers encounter those products virtually everywhere. Therefore, the challenge is not simply one of personal responsibility. Biology, environment, culture, sleep, stress, and genetics all influence how people respond to food. Some individ
More from Fork U with Dr. Terry Simpson
With all the spices we have access to, it is amazing how bland recipes have become. I have many cookbooks, some from great chefs, television personalities, and friends. What I am always surprised by is how bland the food has become. People seem to think a bit of salt, pepper, maybe onions, and garlic provide the spices one needs. Perhaps it is because some associate spice with heat. Mostly because many have never experimented with some of those great warm spices available. A pinch of coriander, some freshly ground cumin, a little cardamom, or a touch of cinnamon can turn an ordinary dish into something remarkable. And the most astonishing part is that these spices financed voyages around the world, built cities, created fortunes, and caused people to kill one another. Without the spice trade, it is safe to say that the United States, as we know it, would be vastly different from what it is now. The money loaned to the United States, when we were a fledgling country, came from the wealthy spice merchants from what was considered one of the great hyperempires of the world, based in Amsterdam. But before we go to the birth of the United States, let me take you to the meatball.
Tea: The Drink That Built an Empire—and Helped Break One China had the tea. Britain had the appetite. John Hancock had a business to protect.
MesoAmerica and Chocolate In our series looking at foods that built civilizations, today we are going to stay in the Americas with chocolate. Chocolate has been used as currency, consumed by kings, incorporated into religious ceremonies, and prescribed as medicine. Today, it is a multibillion-dollar industry that wants you to believe that eating chocolate is an act of preventive cardiology. I mean, why not? They convinced us to give chocolate to people we love, eat it when we are happy, when we are sad, when only the dog understands us. Don’t feed chocolate to your dog. And we have done all this with a bitter seed that most of us would probably spit out if we tasted it straight from the tree.
I’ve been doing a series about foods that built civilizations. In this episode, we are talking about the potato. It is difficult to imagine that thousands of years ago, people constructed large buildings, managed rivers, built monuments, and created art. We have glimpses of these civilizations through stories, archaeology, and the structures they left behind, but much of their history has been lost. Imagine, we don’t even know where Cleopatra or Alexander the Great are buried, yet we know their stories. As European powers conquered Indigenous peoples, their languages, cultures, and oral traditions were suppressed. When a language disappears, so are the stories preserved within it. Our clues come from archaeology when we uncover a monument, a building, or an ancient settlement. In the Andes, the potatoes they cultivated were not the Russets, Yukon Golds, or fingerlings you find in the store today. Different colors, shapes, and textures. Adapted to survive the elevations, temperatures, and growing conditions. Biodiversity protected their food supply against frost, disease, and changing environmental conditions. If one variety failed, another might survive. The ancient wisdom of diversity that Andean farmers developed over thousands of years was lost when the potato eventually reached Ireland.
In our series about foods that built civilization, we talked a lot about grains, from wheat to corn to rice. Today, we are taking you to the ocean, with the civilizations that salmon built. From California to the interior of Alaska, salmon, a staple, allowed people to settle into villages, develop complex social networks, art, and trade routes. Those trade routes are as large as the ones in the Mediterranean. Some tribes built communal homes and developed complex art and language. Some were Seafaring tribes with canoes up to 60 feet long that traveled across oceans. All because there was a fish that would return in large numbers to streams and rivers, reliably, predictably. So predictable, the people could build their lives around salmon runs. So much so that some built a calendar not only with lunar cycles, but also with the return of the salmon. Civilizations have always gathered around food and water. The Mediterranean connected people who grew wheat and olives, giving people time to make wine, mine copper, build ships, trade with their neighbors, and occasionally go to war with them. Asia had rice and grain near the great river systems. The reliable calories from rice and grains allowed villages to become cities and to travel by water to trade. Today we are going to my home, from the Ventura River in California to my home state of Alaska.